1. Field of the Invention
Embodiments of the present invention relate to reducing latency of prepaid group communication sessions within a wireless communications system.
2. Description of the Related Art
In wireless telecommunication devices, such as cellular phones, PDAs, mini-laptops, and advanced pagers, the devices typically communicate over long distances by bridging telephone calls through existing cellular telephone networks and passing data packets across the network. These wireless devices often have limited to significant data processing and computing capability, and can accordingly send and receive software programs, in addition to voice, across the telephone network.
There exists a wireless telecommunication service that provides a quick one-to-one or one-to-many communication that is generically referred to as “Push-To-Talk” (PTT) capability. The specific PTT group of recipient devices for the communicating wireless device is commonly set up by the carrier. A PTT communication connection is typically initiated by a single button-push on the wireless device that activates a half-duplex link between the speaker and each member device of the group and once the button is released, the device can receive incoming PTT transmissions. In some arrangements, the PTT speaker will have the “floor” where no other group member can speak while the speaker is speaking. Once the speaker or floorholder releases the PTT button, any other individual member of the group can engage their PTT button and they will have the floor.
There also exist “pre-pay” service plans for wireless devices. Where a customer chooses such a plan, the customer puts money into their account, and that account is debited according to the user's service usage. When such a customer attempts to place a call, many time-consuming steps are executed before the call goes through. The application server that the wireless device communicates with receives a call initiation trigger from the wireless device and then queries an online charging system (OCS). The OCS checks the user's available balance, and if the user has a sufficient balance, the OCS sends an indication to the application server that the user is permitted make the call. The application server then forwards the call invitation (e.g., announce message) to the target user's communications device.
Accordingly, the application server waits to receive the authorization and available balance for the originator of the call before attempting to bring the target user into the call by sending the invite to the target user's wireless communication device. The verification of the originator's ability to pay for the call adds extra processing delays as well as delays due to message exchanges between the application server and the online charge server in the call setup procedure for the call. This increases initial call setup latency and initial media latency for such a pre-pay customer.
While call setup is slightly delayed due to the verification procedure in pre-paid communication sessions, most communication sessions do not undergo significant performance degradation due to such delays. However, such delays may be less acceptable in delay-sensitive communications (e.g., PTT sessions, etc.). Thus, the experience of a pre-paid PTT customer may be degraded due to call setup delays associated with the above-noted verification procedure.